Process for preparing tocopherol concentrates

Details Process for preparing tocopherol concentrates Process for preparing tocopherol concentrates

1999-12-29

2002-07-02

Solola, T. A. (Department: 1626)

Organic compounds -- part of the class 532-570 series

Organic compounds

Heterocyclic carbon compounds containing a hetero ring...

C549S513000

Reexamination Certificate

active

06414166

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to a simple and effective process for preparing tocopherol concentrates.
BACKGROUND OF THE INVENTION
Vegetable oil deodorizer sludge contains about 5 to 20% of tocopherols, and therefore is an important raw material for producing vitamin E and the natural antioxidants. However, the deodorizer sludge often contains substantial amount of free fatty acids, glycerides, phytosterols and hydrocarbons. The contents of free fatty acids are considerably high, ranging from about 30 to 60%. Thus, when we prepare the tocopherol concentrates from the vegetable oil deodorizer sludge, it is essential to remove these substances first, especially the free fatty acids.
Many methods for preparing tocopherol concentrates have been reported. Most of these methods involve esterification (especially methyl esterification) and high-temperature molecular distillation. The steps for such methods are very complex and require using the expensive distillation equipment and operating at a high temperature which might be a disadvantage to the heat-labile tocopherols. These methods can be mentioned as, for example, Mao and Tsen's method (Investigation on the
Conditions for the Preparing of High-Purity Vitamin E Concentrate from Soybean Oil Deodorizer Distillate.
Journal of the Chinese Agricultural Chemical Society.
33(6): 686-697, 1995, Taipei), and the methods disclosed in U.S. Pat. No. 4,454,329. (Y. Takagi and Y. Kai, Process for preparation of tocopherol concentrates. Jun. 12, 1984); U.S. Pat. No. 5,190,618 (A. G. Md. Top, et. al., Production of high concentration tocopherols and tocopherols from palm-oil by-products. Mar. 2, 1993); U.S. Pat. No. 5,616,735 (T. K. Hunt, Recovery of tocopherols. Apr. 1, 1997); U.S. Pat. No. 5,627,289 (L. J. Hilden, et. al., Recovery of tocopherol and sterol from tocopherol and sterol containing mixtures of fats and fat derivatives. May 6, 1997), and U.S. Pat. No. 5,703,252 (T. K. Hunt and J. Schwarzer, Recovery of tocopherols. Dec. 30, 1997), etc. All these methods are principally using esterification in combination with molecular distillation. These processes are all complicated, time-consuming and require high temperature treatment and expensive equipment.
On the other hand, U.S. Pat. No. 4,594,437 (Sampathkumar, Jun. 10, 1986) disclosed a process for recovering tocopherols from deodorizer sludge by using large amounts of solvent and urea to remove free fatty acids. According to the claim 1 of this patent, the amount of urea used is 5 to 25 equivalents of the fatty acids, and the amount of the solvent is 1 to 75 equivalents of urea. In additions, this method also includes heating at about 70° C. and cooling to 0° C., and this is very energy consuming. Furthermore, in order to recover the tocopherols, it needs to use other solvents to extract the tocopherols, for example, CHCl
3
in Example 1; hexane in Example 2; CH
2
Cl
2
in Example 3.
In additions, Lee, et al. reported a method for the concentration of tocopherols from soybean oil sludge by supercritical carbon dioxide [
J Am. Oil Chem. Soc.
68(8): pp. 571-573, 1991]. However, this method also requires esterification of free fatty acids and an expensive special equipment for the supercritical carbon dioxide extraction.
SUMMARY OF THE INVENTION
The present invention provides a simple and effective process for preparing tocopherol concentrates. The method is characterized by precipitating the free acids in a mixture containing tocopherols and free fatty acids as the alkali metal salts thereof in a specific solvent that cannot, practically, dissolve the alkali metal salts of fatty acids, and recovering the tocopherols from the supernatant by removing the solvent. The specific organic solvents include acetone, ethyl acetate, dimethylformamide, acetonitrile and their mixtures.
BRIEF DESCRIPTION OF THE DRAWINGS
Table 1 The main compositions of the soybean deodorizer sludge and some tocopherol concentrates.
Table 2 The result of gas chromatographic analysis revealed that the tocopherol content with solvent as DMF, acetonitrile or ethyl acetate
Table 3 The result of gas chromatographic analysis revealed that the tocopherol content with NaOH


REFERENCES:
patent: 3335154 (1967-08-01), Smith et al.
patent: 4454329 (1984-06-01), Takagi et al.
patent: 4594437 (1986-06-01), Sampathkumar
patent: 5190618 (1993-03-01), Top et al.
patent: 5616735 (1997-04-01), Hunt
patent: 5627289 (1997-05-01), Jeromin et al.
patent: 5703252 (1997-12-01), Hunt et al.
Lee et al., “Concentration of oTocopherols From Soybean Sludge by Supercritical Carbon Dioxide,” JAOCS, vol. 68 (No. 8), p. 3, (Dec. 29, 1991).
Mau et al., “Investigation on the Conditions for the preparation of High-Purity Vitamin E Concentrate from Soybean Oil Deodorizer Distillate,” national Chung Hsing University (Taiwan, ROC), p. 12, (Dec. 29, 1995).

Affiliated with

Also associated with

Rating

Process for preparing tocopherol concentrates does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for preparing tocopherol concentrates, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for preparing tocopherol concentrates will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2899954